[U-Boot] [PATCH 4/5] sf: Update SST25* flash params of supported read commands

[Bin Meng]

Hi Jagan,

On Tue, Oct 28, 2014 at 3:09 PM, Jagan Teki <jagannadh.teki at gmail.com> wrote:
> Hi Bin,
>
> On 28 October 2014 06:52, Bin Meng <bmeng.cn at gmail.com> wrote:
>> Hi Jegan,
>>
>> On Tue, Oct 28, 2014 at 2:08 AM, Jagan Teki <jagannadh.teki at gmail.com> wrote:
>>> What is this, by defining RD_EXTN the fastest read cmd will pick based
>>> on controller mode_rx
>>> Why this RD_SLOW again? does this means the specific flash part will
>>> only support slow read?
>>
>> Correct, the SST25* (except SST25VF064C) only supports the array read
>> (03h) and fast array read (0Bh) command.
>
> Then make sure to add 0 for picking up fast read(default) and if you
> need a slow read
> to be operate all the ways just define RD_EXTN flash side and
> SPI_OPM_RX_AS (but
> which is not a recommended one as we have fast read supporting).

I am not sure if I understand it correctly. Do you mean adding ARRAY_FAST to:

enum spi_read_cmds {
        ARRAY_SLOW              = 1 << 0,
        DUAL_OUTPUT_FAST        = 1 << 1,
        DUAL_IO_FAST            = 1 << 2,
        QUAD_OUTPUT_FAST        = 1 << 3,
        QUAD_IO_FAST            = 1 << 4,
+       ARRAY_FAST              = 1 << 5,
};

then changing the SST flash parameters like this:

-       {"SST25WF080",     0xbf2505, 0x0,       64 * 1024,    16,
 0,          SECT_4K | SST_WP},
+       {"SST25VF040B",    0xbf258d, 0x0,       64 * 1024,     8,
RD_SLOW | ARRAY_FAST,          SECT_4K | SST_WP},

I originally intended to do this, however I am not sure whether I
should give ARRAY_FAST to 1 << 5 (meaning the fastest read command
than any others). Maybe it should be 1 << 3? Also I need update every
spi controller driver to initialize spi->op_mode_rx to something
meaningful. Currently only ti_qspi.c has such initialization
(slave->op_mode_rx = 8;).

Regards,
Bin